Clermont Auvergne had to settle for a draw against Racing 92, while Lyon held on to beat Pau in a thrilling day of Top 14 action.
Maxime Machenaud nailed a late penalty as Clermont Auvergne failed to capitalise on Toulouse's rare slip-up after being pegged back in a 31-31 Top 14 draw by Racing 92 on Sunday.
Leaders Toulouse lost a top-flight fixture for the first time since September at Toulon a day earlier, which left the door ajar for second-placed Clermont to close the gap.
Such an eventuality appeared a distinct possibility as tries from Wesley Fofana, Apisai Naqalevu, Remy Grosso and John Ulugia helped the home side to a 25-13 lead.
An Olivier Klemenczak try on the stroke of half-time got Racing back into the contest, but a pair of Morgan Parra penalties sandwiched a Machenaud three-pointer to seemingly leave Clermont in the driving seat.
However, a penalty-try with 10 minutes remaining, which also saw Damien Chouly sin-binned, brought Racing within striking distance and Machenaud kept his cool with a 78th-minute penalty to earn the visitors a draw.